For several decades, the quark model suggested 60 years ago was a powerful and successful tool to understand and predict properties of hadronic states in QCD. However, since 2003, when the Belle Collaboration discovered the X(3872), an enigmatic state in the spectrum of charmonium with the properties at odds with the predictions of the quark model, a new era in the spectroscopy of hadrons containing heavy quarks began. Since then, many new states in the spectrum of charmonium and bottomonium have been discovered that do not fit into the quark model scheme and qualify as exotic states. Most of them reside near strong thresholds that leave imprints on their nature and properties. After a very general introduction to the physics of ordinary and exotic hadrons I will discuss various phenomena (coupled channels, multi-body dynamics, interplay of the quark and hadronic degrees of freedom, and so on) that need to be taken into account in theoretical approaches to reliably extract the information contained in the data on exotic hadrons with heavy quarks. Then, I will discuss particular examples of the effective field theory approach applied to various recently discovered exotic hadrons with heavy quarks.

Biography

Dr. Nefediev works mainly on theoretical studies in hadronic physics, analysis and interpretation of the experimental and lattice data, prediction of new hadronic states and their properties, and so on. He obtained his PhD degree in 1999 at the Institute of Theoretical and Experimental Physics (Moscow, Russia). From 2000 to 2002, he was a postdoctoral researcher at the Instituto Superior Tecnico (Lisbon, Portugal). From 2002, he took a permanent position as a Senior Scientist at the Institute for Theoretical and Experimental Physics (Moscow). In 2017, he obtained his second scientific degree adopted in Russia, Doctor of Sciences (habilitation). In 2018, he occupied a permanent position as a Leading Scientist at P.N.Lebedev Institute of the Russian Academy of Sciences (Moscow). Since 2022, he has been holding the position of a Scientific Advisor at the Institute Josef Stefan, Ljubljana, Slovania.？

Inviter

Feng-kun Guo